Excerpt from an article recommended by Matt Levito at http://www.mykarateclub.co.uk/history-more/

Understanding the principles and philosophy of traditional Karate-Do is essential for all its participants. Karate is often sensationalized by some people as a brutal method of fighting. The purpose, objectives, and goals of Karate should not be limited to its physical appearance. The relationship between a lifetime of martial arts and the necessity of using Karate skills in a mature and responsible way has been taught for many centuries.

Unfortunately, sensationalism and commercialization of martial arts together with accelerated exportation of instructors to the West, seems to have resulted in a loss of these concepts all too often. Karate should not be practiced solely as a fighting technique. In order to make effective use of the fundamental techniques and to maximize development of a Karateka's skills, the philosophical aspect of traditional Karate as an art of self-defense must not only be recognized but must also play a prominent role.

Traditional Karate is a martial art and students should train with an appropriate attitude exemplifying the goals and principles of the martial art. A strong emphasis should be placed on metaphysical aspects of the art rather than on the physical techniques. Proper training must apply to the body and the mind in conjunction.

Traditional Karate systems emphasize character building aspects as a foremost principle with respects for instructors, colleagues, and opponents alike. Principles taught to students can be summarized by the following words: character, sincerity, effort, etiquette, and self-control. This is the true way for a martial art such as Karate-Do.

Consequently, a true follower of Karate-Do should strive for perfection in both the philosophical and physical aspects of the art. This will particularly enhance all Karateka's abilities in the execution of Karate techniques in practice, competition, or self-defense. Karate-Do (the way of the empty hand) implies more than is immediately obvious. In an often quoted passage Gichin Funakoshi described the state of mind and body to which the Karate-ka (Karate practitioner) should aspire. He used the image of a mirror: "As a mirror's polished surface reflects whatever stands before it; and a quiet valley carries even small sounds, so must the student of Karate render their mind empty of selfishness and wickedness in an effort to react appropriately to anything they might encounter. This is the meaning of kara in karate."

As a result, the name Karate was chosen to convey the ideas of emptiness since students are expected to empty their minds of all thoughts and emotions in pursuit of their Budo (martial art way, or way of the warrior). An incorrect mental attitude would inevitably have an adverse effect on even the most skilled technician, and Karate-ka must train to the point of automatic reaction where external considerations will not interfere with their calm mental state of impassivity or emptiness. This is not to say that Karate training is done in a mindless state, but rather is free from inhibiting thoughts of doubt, confusion, or fear.

Analogies to water are also referred to in many martial art readings' such as: "Smooth water reflects the image of all that is within its range. If the Karate-ka's mind is in such a state, they will be able to immediately comprehend their opponent's movements and respond appropriately. However, if the surface is disturbed, the result will be a distortion of the images it reflects with the equivalent results on the Karate-ka's mind."

Another analogy refers to the mind as being like the moon: "As the moon shines on everything within its range the Karate-ka is to be constantly aware of the totality of the opponent and their movements. If the clouds were to block the light, a correct appreciation of the opponent's movements would become more difficult to assess and the right approach would escape. The will must connect mind and body so that the mind does not function in isolation and there can be a physical reaction in unison with the order given by the mind."

Another link between mental and physical components is defined as focus (kime). Focus is the art of concentrating all one's mental energies on a specific target in an instant. The analogy has been drawn of a person trapped in a blazing room being able to produce on demand the strength to knock down the door, a task normally found quite impossible. Kime involves a spontaneous concentration of energy, often referred to in the martial arts as "chi" or "ki," which flows from the pelvic region to the extremities and points of contact. To generate maximum speed, the striking limb is kept relaxed until immediately before impact. On impact, the muscles of the body contract and the student emits a "kiai" which is propelled by the muscles of the lower diaphragm.

Psychologically this assists with a total commitment to the technique and the muscular effort involved adds to the power produced. It should be noted that the "kiai" need not produce any sound. The object is to transmit, via the correct use of stance, breathing, and timing, the muscular power of the whole body down a striking limb moving at maximum speed, to focus on a given object. In conjunction with the mental concentration, this exertion of energy is instantaneous and is collectively withdrawn in the next instant in preparation for another technique.